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precision gps Android app

Precision GPS

The typical accuracy of a GPS reading on your Andoid device (or a dedicated handheld or car GPS receiver) is typically 5 to 10 meters. This may seem adequate for most applications, but there are many cases where greater accuracy is needed. What's more, the reported accuaracy of each measurement is actually an underestimate of the true accuracy.

 

Precision GPS uses your device's GPS sensor to measure your location more accurately than is possible with typical GPS apps. Normally, software on your Android device determines your location from individual GPS readings (from a set of satellites). This is fine if you are interested in getting your location to within about 10 meters. However, it is possible to do better than this if you average many readings at a particular location.


This app is designed to do just that - average many readings of a stationary Android device to get a more accurate location; it actually calculates a weighted average, accounting for the accuracy of each reading. The trade-off is time. You will need to wait a least a few minutes to get a high accuracy average location.


Precision GPS displays the following information on the main screen:
-'start/stop' button,

-'reset' button,

-current latitude and longitude,

-'round' number,

-elapsed time,

-number of GPS satellites in view,

-number of GPS satellites employed in fixing location,

-signal-to-noise ratio of signal from each satellite,

-accuracy of the current readings,

-weighted average (mean) latitude and longitude,

-graph of the current latitude and longitude (white connected points) and the average value (red dot),

-bounding 'scale box' (green) around mean position with a width and a height of 2 meters.


The 'reset' button is inactive while readings are being taken. It can be used after the 'stop' button is pressed. If the measurements are stopped and then started again without pressing the reset button, then only the 'elapsed time' value is reset.


The latitude and longitude values are shown on the graph. Latitude increases toward the top and longitude toward the right, as in a map. The graph automatically rescales to include the extreme values of longitude and latitude each time it updates the graph (every four seconds). The green scale box is not always square in shape, since the graph latitude scale is not necessarily the same as the graph scale in longitude.


A 'settings' screen provides an option to keep the screen continuously on while the app is running. It also provides an option to change the interval between measurements.

 

The pro version is ad-free, adds elevation information, UTM coodinates, an option to run the app in the background, and options to save and email measurements.

 

Both versions include localization for French, German, and Spanish.


Applications of Precision GPS include geocaching, emergencies, surveying a property, observational astronomy, and archaeology.


Free and pro versions of this app are available on the Google Play market:


Precision GPS Free

Precision GPS Pro


Example graph of latitude versus longitude showing individual connected data points (white), weighted average location (red), and scale box centered on average loction (green). This plot is the result of data collected over a period of about 5 minutes. North is towards the top and east is to the right.

Same as above but for data collected over 15 minutes. Notice the much different scaling of this graph.

Screenshots

Screenshot of Precision GPS Pro.